Dude, both my keys are unbranded ie been replaced before, I've owned many different types of key, I would say I'm pretty good at using them... two have broke within less than a month of ownership! one didn't even do one turn in the ignition!
regardless of whether it's an issue or not (which if it happens twice then it kind of is), does no-one make or have ever made uprated 'unbreakable' replacements, I come from the Mazda RX7 world and lots of normal interior parts have an 'unbreakable' aftermarket counter part, would guess its similar in Toyota/Lexus world?